I am pretty sure the answer to your question is No.Kdenlive uses the ffmpeg application to render video. I note that in ubuntu 14.04 kdenlive is configured to use avconv (a fork of the ffmpeg project) ( /usr/bin/avconv). This is because Ubuntu has gone with avconv instead of ffmpeg after the schizm. You can configure the location of your ffmpeg from Settings>Configure Kdenlive>Environment and you could use this to use ffmpeg or avconv as your rendering application I guess. So to this limited degree you can use a different tool to render.